KEY POINTS:
The Electricity Commission chairman, Peter Harris, has announced the decision to approve Transpower's latest version of its plans to build a high-voltage AC line from Whakamaru near Taupo to Pakuranga.
The plan differs from previous ones in that the line would be run at 220 kilovolts, not 400.
This reduces the initial outlay by about $200 million, allowing the plan to pass the Commission's Grid Investment Test (GIT).
Other alterations include the extension of the line from Otahuhu to Pakuranga to increase reliability of supply, and a small extension of undergrounding from a point on the ridge at the top of Sandstone Road to the middle of the Whitford Valley near the golf course and vineyards. A 1.2ha substation would be built there.
In about 2040 the line would be upgraded to 400KV if the demand required it. This would depend on a number of unpredictable factors including growth in demand, future electricity generation, site location and other grid upgrades.
The pylons to allow the line to operate in 2040 at 400KV would be built now. Most of the 427 pylons required would therefore be 70m on a base of 15m at 400m spacing. The height of 70m is required to allow a minimum of 12m wire height at the sag point and prevent voltage arcing to the ground.
They would go from the large substation in the Whitford Valley across the Brookby and Clevedon Valleys, Hunua and down the Waikato - 190km.
The plan involves compensating affected landowners for the taking of a 65m-wide easement strip for the line. Owners of adjoining land further than 65m from the line would not be compensated.
This is defined by the Public Works Act. After approval, Transpower would take the land under the act. This means dwellings could be 25m from the pylon base.
There has been and will continue to be substantial criticism of this plan, particularly of the huge pylons which would tower above North Head (64m), the Harbour Bridge (67m), the Beehive (48m) and any dwellings nearby.
That these are to be imposed 30 years before they are required, if at all, has been criticised. Assuming the plan is "called in" by a new Minister for the Environment it still has to go through a panel of inquiry, so these factors may change.
The process of the commission approving this proposal ahead of alternatives, especially upgrading existing lines, has been criticised and may be the subject of a judicial review.
This would centre on the very narrow cost difference between upgrades of existing lines and the new line, only $11 million in an $800 million project - especially as buying the required land, or taking it under the Public Works Act, will be much more expensive than allowed for in the proposal.
Transpower has already spent $120 million dollars buying a third of the required properties - the easy third, it could be argued.
The commission received many submissions on the narrow easement strip width arguing that it should be substantially increased. This is crucial to the plan, as if it was wider the cost would be greater by hundreds of millions of dollars.
And it would fail the commission's test by a wide margin, upgrades being much more competitive.
There are several powerful arguments for a wider easement strip.
Consideration of a pylon falling over - "pylon topple" - demands at least a 200m-wide strip. Passage of the line through forest results in a similar width to allow for falling trees.
Noise from line humming, especially in wet weather, argues for at least 200m, as do shadow effects.
The most sinister arguments, especially in the long-term, centre around the adverse health effects of the alternating electro-magnetic fields involved. These fields are very large around such lines, hundreds of metres across.
The nature of these risks has now been widely publicised and concerns not just the most well known one of childhood leukaemia but also increased risks of miscarriage, brain cancer, adult leukaemia, links to suicide and depression, and concerns about breast cancer and motor neurone disease, among others.
The website www.notowers.co.nz provides more information.
To be relatively clear of these risks an easement strip of 300m would be required for 220KV and 500-600m for 400KV, subject to current loads being normal for such lines.
Lastly, just simple aesthetics - what reasonable people should be expected to have imposed on them - argues for an easement strip width of 500m for such huge pylons.
The commission ducks the argument concerning health risks by referring to the limits set by the New Zealand National Radiation Laboratory, and observing that the new line would emit a tenth of those limits at the strip edge. But only diehards believe those limits now.
They were set in April 1998 by the International Committee for Radiation Protection, which took into account only field strengths that would cause shocks or burns, and ignored evidence concerning long-term effects because of their uncertainty at that time.
It said then that the limits were "not intended to be a complete system to protect the public" and advocated caution.
All the evidence points towards a safe limit about one three hundredth of the international committee's limit, meaning the field from the line would be about 30 times stronger than this at the strip edge.
Many countries have adopted a precautionary approach because of this - undergrounding more, wider easement strips, phasing in new standards and responding to community concerns.
With this background, simple common sense advises a wider easement strip of 500-600m for the line. The majority of the commission have ignored these arguments and the commission has therefore failed in its duty to the nation.
To his credit, one commissioner, Graham Pinnell, did dissent on economic and security grounds from the approval, favouring upgrades.
Affected New Zealanders now pin their hopes on the combined Councils' Board of Inquiry and the Environment Court.
If that process is denied them by a ministerial call-in then they will be hoping the Cabinet will allow a fair hearing by appointing a truly independent panel, chaired by a judge, to make the final decision.
It is inconceivable that an Environment Court in New Zealand in 2008, or such an independent panel, would allow such a narrow easement strip.
The resulting wider easement strip means that the project would then fail on economic grounds against competing upgrades.
One does not need that argument to conclude that the plan lacks basic common sense. It would appear now that only a senior politician, perhaps this Prime Minister or the next one, who takes pride in simple common sense can arrest the folly of the Electricity Commission and Transpower before the Environment Court or the independent panel does. The Cabinet's choice of panel members will be a test of the value it places on justice.
* Dr Robin Smart is a member of the health committee of New Era Energy, an umbrella organisation including groups in Auckland and Waikato opposing the new line.
